Material processing apparatus

ABSTRACT

A material processing apparatus comprises a material processing machine pivotably coupled to a base by a pivot joint that allows pivoting movement of the material processing machine about a pivot axis that is perpendicular to a ground surface. The pivot joint comprises an upper joint part coupled to the material processing machine, and a lower joint part coupled to the base, the upper and lower parts being coupled together by a spindle that defines said pivot axis and about which the upper joint part is rotatable with respect to the lower part. The pivot joint includes a non-contact rotation sensor for detecting an angular position of the upper joint part with respect to a reference position.

FIELD OF THE INVENTION

This invention relates to material processing apparatus. The inventionrelates particularly to conveyors and especially, but not exclusively toradial conveyors.

BACKGROUND TO THE INVENTION

A radial conveyor is a type of material processing apparatus andcomprises a conveyor mounted on a wheeled support structure, the wheelsbeing configured to allow the conveyor to move in a radial, or arc-like,manner about a centre point. Like other material processing apparatus,it is common to transport radial conveyors in a container such as ashipping container. However, even though radial conveyors can usuallyreconfigured for stowage, they can still be too long and/or too high tofit into standard shipping containers and the like.

Another issue with radial conveyors is how to control its radialoperating angle. A conventional approach is to place stops in the pathof part of the machine and to halt radial movement of the conveyor whena stop is detected. However, if an operator forgets to place the stops,or places them in the wrong position, the conveyor will be incorrectlypositioned.

It would be desirable therefore to provide an improved radial conveyorthat mitigates the problems outlined above. It will be understood thataspects of the invention described herein may be used with othermaterial processing apparatus.

SUMMARY OF THE INVENTION

A first aspect of the invention provides a chassis comprising a firstchassis part coupled to a second chassis part by a coupling that allowsrelative pivoting movement between the first and second chassis parts toallow an intermediate section of the chassis to be raised or lowered.

A second aspect of the invention provides a conveyor apparatuscomprising:

-   -   a chassis having a longitudinal axis;    -   a conveyor supported on the chassis, the conveyor being movable        into and out of a deployed state,    -   wherein, when said conveyor is out of said deployed state, said        conveyor is movable with respect to said chassis in a        longitudinal direction.

A third aspect of the invention provides a radial conveyor apparatuscomprising a conveyor supported on a chassis, the chassis beingpivotably coupled to a base by a pivot joint that allows pivotingmovement of said chassis and said conveyor about a pivot axis that isperpendicular to a ground surface, wherein said pivot joint comprises anupper joint part coupled to said chassis, and a lower joint part coupledto said base, said upper and lower parts being coupled together by aspindle that defines said pivot axis and about which the upper jointpart is rotatable with respect to the lower part, and wherein said pivotjoint includes a rotation sensor for detecting an angular position ofsaid upper joint part with respect to a reference position.

Preferably, said coupling includes a locking device that is operablebetween a locking mode in which it prevents said relative pivotingmovement between the first and second chassis parts, and an unlockedmode in which it allows said relative pivoting movement.

Preferably, said coupling includes a first pivot axis runningtransversely of the chassis and being located between first and secondends of the chassis, said relative pivoting movement comprising movementabout said pivot axis.

Preferably, said first and second chassis parts are pivotable between anoperating state in which said intermediate section is relatively raised,and a lowered state in which said intermediate section is lowered withrespect to said operating state.

Advantageously, in the locking mode, the locking device locks thechassis in the operating state, and in the unlocked mode, the lockingdevice allows said the chassis parts to adopt the lowered state.

In typical embodiments, each chassis part comprises at least one wheelassembly, said intermediate section being located between said at leastone wheel assembly of the first chassis part and said at lease one wheelassembly of the second chassis part. Said second chassis part typicallyhas a wheel axis, and wherein said relative pivoting movement involvespivoting movement of said second chassis part about said wheel axis withrespect to the first chassis part. Said second chassis part ispreferably configured such that its centre of mass is located on thesame side of its wheel axis as said intermediate section.

In preferred embodiments, said first chassis part includes a linkstructure that is pivotably coupled to the second chassis part forpivoting about said first pivot axis. Said link structure may bepivotably coupled to the first chassis part for pivoting about a secondpivot axis that is longitudinally spaced apart and parallel with saidfirst pivot axis. Preferably, said locking device is coupled between thelink structure and the second chassis part and wherein, in the lockingmode, the locking device rigidly fixes the link structure with respectto the second chassis part preventing pivoting of said link structureabout the first pivot axis, and in the unlocked mode, the locking devicepermits pivoting of said link structure about the first pivot axis.Preferably, the link structure pivots downwardly as the chassis movesfrom the operating state to the lowered state, and pivots upwards as thechassis moves from the lowered state to the operating state.

In preferred embodiments, said locking device comprises at least onebolt with at least one corresponding nut, and wherein said at least onebolt disposed perpendicular to the longitudinal and transversedirections of the chassis, and wherein the position of said at least onenut on the respective bolt determines the amount of said relativepivoting movement. Said at least one bolt is preferably long enough toallow said at least one corresponding nut to be positioned on therespective bolt to allow the pivoting movement of the chassis betweenthe operating and transport states.

In preferred embodiments, in said deployed state, said conveyor ispivotably coupled to said chassis, said apparatus further including anextendible conveyor support coupled between said conveyor and saidchassis and operable to raise or lower a first end of said conveyor bypivoting said conveyor with respect to said chassis. Preferably, whensaid conveyor is out of said deployed state is disposed substantiallyparallel with said longitudinal axis. Typically, said pivotable couplingof said conveyor is provided by a pivotable support structure, typicallylocated at a second end of said conveyor, and wherein, when saidconveyor is out of said deployed state, said pivotable support structureis decoupled to allow movement of said conveyor with respect to saidchassis in said longitudinal direction.

When said conveyor is out of said deployed state, it may be supported byat least one roller and/or at least one slide provided on said chassisfor facilitating said movement of said conveyor with respect to saidchassis in said longitudinal direction.

When said conveyor is not in said deployed state, said conveyor supportmay be retractable to move said conveyor with respect to said chassis insaid longitudinal direction.

In preferred embodiments, when said conveyor is in said deployed state,an end of said conveyor support is pivotably coupled to said chassis,and when said conveyor is out of said deployed state, said end of saidconveyor support is decoupled from said chassis to allow said conveyorsupport to move with said conveyor in said longitudinal direction.Preferably, at least one track is provided on said chassis, said end ofsaid conveyor support being movable along said at least one track whensaid end of said conveyor support is decoupled from said chassis.

In preferred embodiments, said conveyor includes at least one extendibleconveyor portion, said at least one extendible portion typically beingtelescopically extendible or foldable with respect to said conveyor, andwherein when said conveyor is out of said deployed state said at leastone extendible conveyor portion is folded or otherwise retracted toshorten the length of said conveyor. Preferably, said at least oneextendible conveyor portion comprises an extendible base conveyorportion located at a second end of said conveyor and substantially at afirst end of said chassis, and wherein when said conveyor is out of saiddeployed state, said conveyor is movable with respect to said chassis ina longitudinal direction towards said first end of the chassis.

In preferred embodiments, the sensor is provided on either one of theupper joint part or the spindle. A sensor target is typically providedon the other of the upper joint part or the spindle, the sensor beingdirected at the target. The respective one of the target or the sensormay be provided on an end of the spindle that protrudes into the upperjoint part, preferably on a top face of the spindle. The respectiveother of the sensor or the target may be provided on the upper jointpart at a location facing, and preferably adjacent, the end of thespindle.

In preferred embodiments, said rotation sensor is a non-contact sensor.Preferably said rotation sensor is a magnetic sensor. Said target maycomprise a magnet.

Said upper joint part may include part of a second pivot joint.

In preferred embodiments said rotation sensor is configured to generatean output signal indicative of the angular position of said upper jointpart, said apparatus including, or being co-operable with, a controllerconfigured to use said output signal to determine an angular position ofsaid conveyor and said chassis.

Each aspect of the present invention may be used without either of theother aspects of the invention, or in combination with either one orboth of the other aspects of the invention as would be apparent to askilled person.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are now described by way of example andwith reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a radial conveyor apparatus in adeployed state;

FIG. 2 is a side view of the apparatus of FIG. 1 shown in a firstintermediate state between the deployed state and a transport state;

FIG. 3 is a side view of the apparatus of FIG. 1 in a secondintermediate state between the deployed state and the transport state;

FIG. 4 is a side view of the apparatus of FIG. 1 shown in the transportstate;

FIG. 5 is a detail view of part of the apparatus of FIG. 1 when in saidsecond intermediate state;

FIG. 6 is a detail view of part of the apparatus of FIG. 1 showing inparticular a roller;

FIG. 7 is a detail view of part of the apparatus of FIG. 1 in saidtransport state;

FIG. 8 is a side view of a chassis for the apparatus of FIG. 1, thechassis being shown in an operating state;

FIG. 9 is a perspective view of the chassis of FIG. 8 shown in a loweredstate;

FIG. 10 is a side view of the chassis of FIG. 8 shown in the loweredstate with replacement wheels;

FIG. 11 is an exploded perspective view of a radial joint including aradial position sensing system;

FIG. 12 is an exploded side view of the radial joint of FIG. 11; and

FIG. 13 is a sectioned side view of the radial joint of FIG. 11.

DETAILED DESCRIPTION OF THE DRAWINGS

It is noted that in the drawings features may be omitted for reasons ofclarity or in order that other features are visible, as would beapparent to a skilled person.

Referring in particular to FIG. 1, there is shown a radial conveyorapparatus 10 embodying the invention. The conveyor apparatus 10 is of ageneral type commonly referred to as “radial conveyors”. The conveyorapparatus 10 comprises a conveyor 12, which is optionally extendible,e.g. telescopically extendable and/or with folding parts. The conveyor12 is supported by a wheeled support structure 14. In preferredembodiments, the support structure 14 comprises a chassis 16 and aconveyor support 18 extending between the chassis 16 and the conveyor 12to support the conveyor 12 with respect to the chassis 16. The conveyorsupport 18 is preferably extendable in order to adjust the position ofthe conveyor 12 with respect to the chassis 16, in particular to raiseor lower the height of the conveyor 12. In preferred embodiments, theconveyor support 18 comprises a telescopically extendible frame. Theconveyor support 18 typically includes one or more powered actuators,e.g. hydraulic rams, for extending and retracting the support 18. Forexample, the conveyor support 18 may comprise three sections: a lowersection releasably coupled to the chassis; a middle section, whichconveniently carries actuator(s) e.g. hydraulic ram(s) forextension/retraction; and an upper section. Both the upper and lowersections may be telescopically extendible with respect to the middlesection. In normal use of the apparatus 10, the upper section extends inand out with respect to the middle section to raise and lower theconveyor 12. To effect the transport state, the lower section may beunpinned to allow it to slide up into the middle section to shorten theoverall length of the support 18.

The conveyor 12 has a feed end 20 and a discharge end 22. A hopper 24may be provided at the feed end 20 for loading material (not shown) ontothe conveyor 12. In use, the conveyor 12 receives material at the feedend 20 and conveys the material to the discharge end 22 to be dischargedto a desired location, e.g. a stockpile or a material processingapparatus (not shown).

The feed end 20 of the conveyor 12 is pivotably coupled to the chassis16 such that the discharge end 22 is raised or lowered as the conveyor12 pivots with respect to the chassis 16. Typically, the conveyor 18 ispivotably coupled to the chassis 16 at a first (or rear) end 17 of thechassis 16. The coupling at the end 17 may be provided by a supportstructure 21, which may take any suitable form, for example comprisingone or more pivotable link 21A and one or more extendable structure 21B(e.g. comprising one or more ram). The pitch of the conveyor 12 withrespect to the chassis 16 is determined by the length of the conveyorsupport 18, which is preferably extendible/retractable to hold theconveyor 12 at any one of a plurality of different pitches therebyraising or lowering the height of the discharge end 22.

The conveyor support 18 has one end pivotably coupled to the chassis 16,the other end pivotably coupled to the conveyor 12 and is extendible inits end-to-end direction to allow the conveyor 12 to pivot with respectto the chassis 16. The conveyor support 18 may be lockable in any one ofa plurality of states of relative extension/retraction in order tosupport the conveyor 12 at a desired pitch with respect to the chassis16. In the illustrated embodiment the conveyor support 18 is coupled tothe chassis 16 at a second (or front) end 19 of the chassis 16 oppositethe end 17 at which the conveyor 18 is coupled to the chassis.Alternatively, the conveyor support 18 may be coupled to the chassis 16at any other location spaced apart (along the longitudinal axis of theconveyor) from the location at which the conveyor 18 is coupled to thechassis 16. In the illustrated embodiment the conveyor support 18 iscoupled to the conveyor 12 at a location between the feed and dischargeends 20, 22. Alternatively, the conveyor support 18 may be coupled tothe conveyor 12 at any other location spaced apart (along thelongitudinal axis of the conveyor) from the feed end 20 of the conveyor12. The conveyor support 18 may take any suitable form, for examplecomprising a frame (as illustrated) and/or one or more support members.Conveniently, the conveyor support 18 is telescopically extendible.

The conveyor 12 is extendible/retractable by virtue of comprising atleast one foldable conveyor portion. In the illustrated embodiment, theconveyor 12 has a base conveyor portion 12A (which in this exampleincludes the feed end 20), a mid-portion 12B and a head portion 12C. Thehead portion 12C and base portion 12A are each pivotably coupled, e.g.via one or more hinges, to the mid-portion 12B so that they may each befolded between a deployed state (FIG. 1) for use and a folded state(FIG. 2 shows the head portion 12C in its folded state while FIG. 3shows both the head portion 12C and the base portion 12A in their foldedstates) for storage and transport. Conveniently, the head portion 12Cand base portion 12A may be folded on top of the mid-section 12B, e.g.about a pivot axis that runs perpendicular to the longitudinal axis ofthe conveyor 12. Any conventional folding mechanism (e.g. comprisinghydraulic ram(s) coupled to a linkage) may be provided to effect foldingand unfolding of the foldable portion 12B. In this example, the conveyorsupport 18 is coupled to the conveyor 12 at an end of the mid-portion12B distal the base portion 12A. In alternative embodiments one or moreportions of the conveyor 12 may be telescopicallyextendible/retractable, as well as or instead of having one or morefolding portion. For example, the head portion 12C and/or the baseportion 12A may be telescopically extendible with respect to themid-portion 12B. In other embodiments (not illustrated), the conveyor 12may have only one extendible/retractable portion, or may have more thantwo extendible/retractable portions.

The chassis 16 carries a first set of one or more ground-engaging wheelassemblies 24A, 24B, typically being located at the first end 17 of thechassis 16. In the illustrated example, first and second track typewheel assemblies 24A, 24B are provided although in alternativeembodiments one or more simple (non-track) wheels may be used.

The chassis 16, and therefore the conveyor 12, is pivotable about anin-use vertical axis (i.e. an axis that is perpendicular with the groundsurface upon which the apparatus 10 is supported). This vertical axis istypically located at the first end 17 of the chassis 16. To this end, inthe illustrated embodiment, the first end 17 of the chassis 16 ispivotably coupled to the wheel assemblies 24A, 24B, which are typicallyprovided as part of a bogie. Hence, the chassis 16 and conveyor 12 areable to pivot relative to the wheel assemblies 24A, 24B, or bogie, abouta vertical axis at the first end 17. This pivoting movement may bereferred to as radial movement.

Second and third wheel assemblies 30A, 30B are coupled to the chassis16, one on either side of the chassis 16. Each wheel assembly 30A, 30Bcomprises one or more wheels (which may optionally be of the tracktype). The wheel assemblies 30A, 30B are spaced apart from the wheelassemblies 24A, 24B along the longitudinal axis of the chassis 16.Conveniently, the wheel assemblies 30A, 30B are coupled to the chassis16 at its second end 19. The wheel assemblies 30A, 30B facilitate theradial movement of the chassis 16 as is described in more detailhereinafter. The wheel assemblies 30A, 30B are preferably provided in amanner such that they mirror each other, or are at least capable ofmirroring each other, with respect to the longitudinal axis of thechassis 16. Conveniently, the wheel assemblies 30A, 30B are the same aseach other (other than to the extent that they may in some respects bemirror images of each other to account for their location on oppositesides of the chassis 16). Accordingly any descriptions herein of eitherone of the wheel assemblies 30A, 30B applies to the other. Moreover,while it is preferred to provide a respective one of the wheelassemblies 30A, 30B on each side of the chassis 16, it is possible inalternative embodiments to provide a wheel assembly 30A, 30B on only oneside.

The conveyor apparatus 10 is operable between a use state (FIG. 1) and atransport state (FIG. 4). In the use state, the conveyor 12 typicallyextends obliquely upwards with respect to the longitudinal axis of thechassis 16, with its feed end 20 at a relatively low level (typically ator adjacent chassis-level) and its discharge end 22 at a relativelyraised level. The height of the discharge end 22 and the pitch of theconveyor 12 are determined by the conveyor support 18, and can beincreased or decreased by changing the length of the conveyor support18. Where applicable, the conveyor 12 is extended or unfolded in the usestate. In the use state, the conveyor 12 is supported with respect tothe chassis 16 by the conveyor support 18 and by the second supportstructure 21 at the end 17 of the chassis 16.

In the transport state, the conveyor 12 is moved closer to the chassis16 than when in the use state, preferably being located on top of thechassis 16 and extending substantially parallel with the longitudinalaxis of the chassis 16. Where applicable, the conveyor 12 is retractedor folded in the transport state.

The wheel assemblies 30A, 30B are each operable between a radial state(FIG. 1) and a transport state (FIG. 9). In the radial state, the wheelassemblies 30A, 30B facilitate the radial movement of the chassis 16. Tothis end, the rotational axis of each wheel assembly 30A, 30B isradially displaced from the longitudinal axis of the chassis 16. In thetransport state of the wheel assemblies 30A, 30B, the rotational axis ofeach wheel assembly 30A, 30B is perpendicular with the longitudinal axisof the chassis 16 to facilitate movement of the chassis 16, andtherefore of the apparatus 10, in the longitudinal direction.Accordingly, in the transport state, the apparatus 10 is amenable tobeing towed or pushed, or even of being driven in cases where it isself-propelled.

To effect the radial and transport states, the wheel assemblies 30A, 30Bare movable with respect to the chassis 16 between a deployed state(FIG. 1) and a non-deployed state (FIG. 9). Preferably, each wheelassembly 30A, 30B is pivotably coupled to the chassis 16 to allow it topivot between its deployed and non-deployed states about an in-usevertical axis. Each wheel assembly 30A, 30B comprises one or more wheels32 rotatably mounted on a wheel support structure 34. The wheel supportstructure 34 is pivotably coupled to the chassis 16 to allow the wheelassembly 30A, 30B to pivot between the deployed and non-deployed statesabout an in-use vertical axis. In the deployed state the wheel supportstructure 34 projects outwardly away from the chassis 16 (typicallyextending obliquely to the longitudinal axis of the chassis) to hold thewheel(s) 32 at a location that is laterally spaced apart from therespective side of the chassis 16 (and such that their rotational axisis radially displaced from the longitudinal axis of the chassis 16). Inthe non-deployed state the wheel support structure 34 is foldedalongside the chassis 16 (typically extending parallely or substantiallyparallely to the longitudinal axis of the chassis) to locate thewheel(s) 32 adjacent the respective side of the chassis 16 such thattheir rotational axis is perpendicular with the longitudinal axis of thechassis 16.

Referring in particular to FIGS. 2 to 7, a preferred embodiment of oneaspect of the invention is described in which the conveyor 12 is movableaxially with respect to the chassis 16 in order to reduce the overalllength of the apparatus 10 in the transport state. In particular theconveyor 12 is movable, preferably linearly, in a direction parallelwith the longitudinal axis of the chassis 16. The movement may besliding movement, for example being facilitated by roller(s) and/orslide(s). In preferred embodiments, the conveyor 12 is also foldable toreduce its length in the transport state. It will be understood howeverthat in alternative embodiments, the conveyor 12 may beextendible/retractable by means of one or more telescopic portion aswell as, or instead of, one or more folding portion, while still beingaxially movable in the manner described herein.

In FIG. 2, the conveyor 12 is in a non-elevated state in which it isdisposed substantially parallel with the longitudinal axis of thechassis 16. The head portion 12C is folded onto the mid-portion 12B. Theconveyor 12 rests on the chassis 16 so that the conveyor support 18 andthe support structure 21 are not required to bear the weight of theconveyor 12. In particular it is preferred that the conveyor 12 rests onone or more rollers 40 (see in particular FIG. 7) that are coupled tothe chassis 16. It is preferred that there are at least two sets of oneor more rollers 40, the sets being spaced apart in the longitudinaldirection of the chassis 16. In the illustrated embodiment, there aretwo sets of rollers 40 provided at locations A and B on FIG. 2. In thisexample, each set of rollers 40 comprises two rollers, one forsupporting each side of the conveyor 12. Not only do the rollers 40support the conveyor 12 but they also facilitate linear movement of theconveyor 12 with respect to the chassis 16 in the longitudinaldirection. Alternatively, or in addition, one or more slide mechanisms(not illustrated) may be provided for facilitating linear movement ofthe conveyor 12 in the longitudinal direction.

Assuming that the chassis ends 19, 17 are at the front and rear of thechassis 16 respectively, in FIG. 2, the conveyor 12 is in a relativelyforward position with respect to the chassis 16. As can be seen fromFIGS. 3 and 4, to adopt the transport state the conveyor 12 movesrearward from the forward position with respect to the chassis 16, as isdescribed in more detail hereinafter.

When the conveyor 12 is in use, the couplings between the conveyor 12and the chassis 16 provided by the conveyor support 18 and the supportstructure 21 hold the conveyor 12 in a fixed axial position relative tothe chassis 12 but allow the pivoting movement that is required to raiseand lower the conveyor 12. In order to facilitate axial movement of theconveyor 12 with respect to the chassis 16, these couplings arere-configured or decoupled as is convenient. In preferred embodiments,the support structure 21 is decoupled from the conveyor 12 and/or thechassis 16 as is convenient. For example the pivotable link(s) 21A andextendable structure 21B may be disconnected from the conveyor 12.Similarly, either or both ends of the conveyor support 18 may bedisconnected from the conveyor 12 or chassis 16 as applicable. Inpreferred embodiments, the coupling at lower end 42 of the supportstructure 18 is decoupled to allow relative movement between the end 42and the chassis 16 in the longitudinal direction as is now described inmore detail with particular reference to FIG. 5.

As may best be seen from FIG. 5, the end 42 of conveyor support 18 iscoupled to one or more track 44 provided on the chassis 16. The track 44runs longitudinally of the chassis 16 and has a forward end 46 and arearward end 48 (not visible in FIG. 5). The end 42 of the conveyorsupport 18 includes one or more bearing 50 for riding along the track44. The bearing(s) 50 may for example comprise a boss or otherprotrusion from the support 18, or a roller. During normal use of theapparatus 10, the end 42 is located and fixed at the forward end 46 ofthe track 44, and is pivotably coupled to the chassis 16 to facilitateraising and lowering of the conveyor 12. When the apparatus 10 is movinginto or out of the transport state, the support end 42, facilitated bythe bearing(s) 50 is movable along the track 44 from end 46 to end 48.Preferably the rearward end 48 of the track 44 comprises a seat or otherstop 54 that prevents further movement of the bearing(s) 50 in therearward direction. The track 44 may have a profile between ends 46, 48shaped to guide (i.e. lift and/or lower) the support end 42 past othercomponents of the apparatus 10 as required.

Conveniently, the bearing 50 is part of the pivotable coupling betweenthe conveyor support 18 and the chassis 16 when the chassis 16 is in itsdeployed state. For example, the bearing 50 may include a socket 51 thataligns with a corresponding socket 52 provided on the chassis 16 whenthe support end 42 is located at the forward end 46 of the track 44.When aligned, a pin (not shown) may be inserted into the sockets 51, 52to fix the support end 42 at the track end 46 and to create a pivotablecoupling. The pin may be removed to allow the support end 42 to movealong the track 44 when required.

In the illustrated embodiment, the end 42 of the conveyor support 18 iscomprised of the respective end of two spaced apart bars, each having arespective bearing 50 for running in a respective parallel track 44.

Referring now in particular to FIG. 7, in preferred embodiments, one ormore retaining mechanisms 60 are provided for retaining the conveyor 12on the chassis 16 during linear movement of the conveyor 12. In theillustrated embodiment, the retaining mechanism 60 comprises a track 62provided on the conveyor 12 and running in the longitudinal direction. Acorresponding bearing 64, which preferably comprises a roller, isprovided in a fixed position on the chassis 16 for running along thetrack 62 as the conveyor 12 moves longitudinally with respect to thechassis 16. The engagement between the bearing 64 and the track 62 actsto retain the conveyor 12 on the chassis 16. The bearing 64 is removablymounted on the chassis 16, for example being carried by a removableplate or other base 66 in the illustrated embodiment. In the normalworking mode of the apparatus 10, the bearing 64 is removed to allow theconveyor 12 to be raised and lowered with respect to the chassis 16.Preferably a respective track and bearing assembly is provided at eachside of the conveyor 12.

Starting from the deployed state (FIG. 1), when it is desired toconfigure the apparatus 10 for transport, the conveyor 12 is lowereduntil it rests on the chassis 16 (FIG. 2). Typically, this lowering isachieved by contracting the conveyor support 18. The support structure21 is then decoupled to allow longitudinal movement of the conveyor 12with respect to the chassis 16. The length of the conveyor 12 isshortened, which in the present embodiment involves folding the headportion 12C and base portion 12A onto the mid-portion 12B. Inalternative embodiments, shortening the conveyor 12 may involve foldingjust one portion, or more than one portion, and/or telescopicallycontracting one or more portions as applicable.

The conveyor 12 is moved rearwardly with respect to the chassis 16 (ascan be appreciated from a comparison of FIGS. 2, 3 and 4). Typically,the conveyor 12 is moved rearwardly until the rearward end of themid-portion 12B is substantially in register with the rear end of thechassis 16. The shortening of the conveyor 12 may be performed before,during or after the rearward movement of the conveyor 12, as isconvenient.

In preferred embodiments, the rearward movement of the conveyor 12 isperformed in first and second stages. In the first stage, the lower end42 of the conveyor support 18 is pivotably coupled to the chassis 16,i.e. not decoupled as described above. Accordingly, rearward movement ofthe conveyor 12 in the first stage involves further contraction of theconveyor support 18. Conveniently, rearward movement of the conveyor 12in the first state is effected by powered contraction of the conveyorsupport 18. Alternatively, the conveyor support 18 may contract as theconveyor 12 is moved rearwardly by some other means, e.g. manually or byone or more other powered actuator or vehicle. In the second stage, thelower end 42 of the conveyor support 18 is decoupled from the chassis 16to allow it to move along the track 44, and so to allow the conveyorsupport 18 to move rearwardly with the conveyor 12. During rearwardmovement of the conveyor 12 in the second stage, the end 42 of thesupport 18 moves along the track 44. In the preferred embodiment, thesupport end 42 moves from the forward end 46 to the rearward end 48 ofthe track 44. Conveniently, the stop 54 at the end 48 of the tracklimits not only movement of the support end 42 in the track 44 but alsorearward movement of the conveyor 12. During the second stage, theconveyor 12 may be moved manually or by one or more powered actuator ora vehicle (e.g. a forklift or loading vehicle), as is convenient.

In the transport state (FIG. 4), the apparatus 10 is relatively compactin the longitudinal direction as a result of the longitudinal movementof the conveyor 12, preferably such that its end is substantially inregister with the end of the chassis 16, and its support structure 18,and typically also as a result of the folding or other contraction ofthe conveyor 12 itself. In the transport state, the wheel assemblies30A, 30B are in their non-deployed state, extending alongside thechassis 16 such that the rotational axis of the wheels 32 isperpendicular with the chassis 16.

In order to deploy the conveyor 12 from the transport state, theconveyor 12 is moved forwards until the support end 42 reaches the trackend 46, whereupon the support end 42 is coupled to the chassis 16 tocreate a pivot joint. Advantageously, this forward movement of theconveyor 12 may be effected by extending the conveyor support 18, sincethe support end 42 abuts against the stop 54. In this case, the conveyorsupport 18 may then be contracted so that the end 42 reaches the trackend 46. Alternatively, or in addition, further forward movement of theconveyor 12 may be effected by extending the conveyor support 18 afterthe pivot joint is established. Once the foremost position of theconveyor is reached, the support structure 21 is re-connected such thatfurther extension of the conveyor support 18 causes the conveyor 12 tobe raised.

Referring now in particular to FIGS. 8 to 10 the preferred chassis 16 isdescribed, embodying another aspect of the invention, and which may beused in the radial conveyor 10 together with the longitudinally movableconveyor 12 described with reference to FIGS. 2 to 7, or may be usedseparately, for example with other chassis-based apparatus, e.g.conveyors (radial or otherwise), other material processing apparatus(e.g. screening machines, crushing machines, washing machines and/orrecycling machines).

The chassis 16 comprises a first part 70 coupled to a second part 72,which may conveniently be referred to as the rear part 70 and the frontpart 72, to allow relative pivoting movement between the parts 70, 72that in turn allows an intermediate portion of the chassis 16 to beraised or lowered. In the illustrated embodiment, the second chassispart 72 carries a power plant 73, which may for example include any oneor more of a hydraulic power system, and electrical power system, anengine, and/or controllers as required.

The preferred coupling between the chassis parts 70, 72 includes a pivotaxis PA1 that runs transversely of the chassis 16, perpendicular to thelongitudinal axis of the chassis 16. Any suitable conventional pivotjoint, hinge or coupling mechanism may be used to provide the couplingat pivot axis PA1. The coupling between the chassis parts 70, 72 furtherincludes a locking device 74 that is operable between a locking mode inwhich it prevents the chassis parts 70, 72 from pivoting about the pivotaxis PA1, and an unlocked mode in which the chassis parts 70, 72 areable to pivot about the pivot axis PA1. Pivoting of the chassis parts70, 72 about the pivot axis PA1 allows the intermediate section of thechassis 16 (i.e. a section between the ends 17, 19) to be raised orlowered with respect to a ground surface. In particular, pivoting aboutaxis PA1 allows the chassis 16 to adopt an operating state (FIG. 8), inwhich its intermediate section is relatively raised with respect to theground surface, and a lowered state (FIGS. 9 and 10) in which itsintermediate section is relatively low with respect to the groundsurface. In its locking mode, the locking device 74 locks the chassis inthe operating state and provides a rigid connection between the chassisparts 70, 72. In the unlocking mode, the locking device 74 allows thechassis parts 70, 72 to adopt the lowered state.

In typical embodiments, each chassis part 70, 72 includes one or morewheel assemblies. The pivot axis PA1 is typically located between thewheel assembly(s) of the first chassis part 70 and the wheel assembly(s)of the second chassis part 72. In preferred embodiments, the secondchassis part 72 has a wheel axis that is (or is configurable to be)parallel with the pivot axis PA1 and spaced apart from the pivot axisPA1 in the longitudinal direction. When the locking device 74 isunlocked, the second chassis part 72 is able to pivot about the wheelaxis with respect to the first chassis part 70. In particular, the endof the second chassis part 72 that is coupled to the first chassis part70 is able to be lowered and raised. Accordingly, the intermediatesection of the chassis 16 can be lowered and raised. In preferredembodiments, the second chassis part 72 is configured such that itscentre of mass is located on the same side of its wheel axis as thepivot axis PA1. In preferred embodiments, the pivot axis PA1 is higherthan the wheel axis.

In the illustrated embodiment, the first chassis part 70 comprises thewheel assemblies 24A, 24B, which are typically provided as part of abogie. The second chassis part comprises the wheel assemblies 30A, 30B.In alternative embodiments, either one or both of the chassis parts 70,72 may comprise one or more wheel assembly of any conventional type.

In preferred embodiments, the first chassis part 70 includes a linkstructure 80 that is pivotably coupled to the second chassis part 72 forpivoting about pivot axis PA1. The link structure 80 is pivotablycoupled to the first chassis part 70 for pivoting about a second pivotaxis PA2. The pivot axes PA1, PA2 are longitudinally spaced apart andparallel with one another, each running transversely of the chassis 16,perpendicular to the longitudinal axis of the chassis 16. Any suitableconventional pivot joint or coupling mechanism may be used to providethe coupling at pivot axes PA1 and PA2. The link structure 80 ispreferably rigid. The link structure 80 may take any suitable form. Inpreferred embodiments, the link structure 80 comprises a frame havingspaced apart parallel, longitudinally extending arms 80A, 80B.

In preferred embodiments, the locking device 74 is coupled between thelink structure 80 and the second chassis part 72. In the locking mode,the locking device 74 rigidly fixes the link structure 80 with respectto the second chassis part 72 preventing pivoting of said link structure80 or the second chassis part 16 about the pivot axis PA1. In theunlocked mode, the locking device 74 permits pivoting of said linkstructure 80 and the second chassis part 16 about the pivot axis PA1. Inalternative embodiments, the locking device 74 may be provided in anyother suitable location, e.g. being incorporated into the pivot couplingthat facilitates pivoting about axis PA1.

In preferred embodiments, the second pivot axis PA2 is located above thewheel assembly(s) (which comprise tracks in typical embodiments) of thefirst chassis part 70, in the present example being above the wheelassemblies 24A, 24B (and bogie). In preferred embodiments, the linkstructure 80 pivots downwardly as the chassis 16 moves from theoperating state to the lowered state, and moves upwards as the chassis16 moves from the lowered state to the operating state. In typicalembodiments, in the operating state of the chassis 16 with the lockingdevice 74 in the locking mode, the link structure 80 extendssubstantially parallel with the longitudinal axis of the chassis 16,while in the lowered state the link structure 80 extends downwards fromsaid second pivot axis PA2, oblique to said longitudinal axis.

In preferred embodiments, in the transport state, the wheels 32 of thefront wheel assemblies 30A, 30B that are used in the operating state areremoved and replaced with wheels 82 of a smaller diameter (see FIG. 10),or other lowering track or runner. The smaller wheels 82 reduce theheight of the chassis 16, and therefore of the apparatus 10 of which thechassis is part, in particular at the front.

The locking device 74 may take any suitable form, for example comprisingone or more bolts, nuts, clamps, clips, actuators or the like. Inpreferred embodiments, the locking device 74 comprises one or more bolt84 with corresponding nut 86 for coupling the first and second chassisparts 70, 72 together. In preferred embodiments, the, or each, bolt 84couples the link structure 80 to the second chassis part 72.Advantageously each bolt 84 is vertically disposed, i.e. perpendicularto the longitudinal and transverse directions of the chassis 16. Whenthe nut 86 is tightened, the bolt 84 creates a rigid connection betweenthe chassis parts 70, 72 thereby maintaining the chassis 16 in itsoperating state. When the nut 86 is loosened relative pivoting movementbetween the chassis parts 70, 72 is allowed. With the preferred verticalorientation of the bolt 84, the position of the nut 86 on the bolt 84,when loosened, determines the amount of pivoting movement that isallowed. Preferably, the bolt 84 is long enough that the nut 86 can bepositioned on the bolt 84 to allow the full range of pivoting movementbetween the operating and transport states. Accordingly, the, or each,bolt 84 and nut assembly 86 may be used to control movement of thechassis parts 70, 72 between the operating and transport states. Forexample, an operator (not shown) can cause the chassis 16 to transitionfrom the operating state to the transport state by loosening the nut 86and to transition from the transport state to the operating state bytightening the nut 84 (typically using a suitable power tool).

It will be apparent from the foregoing that preferred embodiments of theinvention allow a chassis and/or an apparatus comprising a chassis to bereduced in length and/or height in order to facilitate transport (orstorage), especially in a standard container. Moreover, transitioningthe chassis/apparatus into and out of its transport state does notrequire significant disassembly of the chassis/apparatus, nor does itrequire the use of lifting equipment such as a crane.

Referring now in particular to FIGS. 11 to 13, there is shown apreferred pivot joint 88, embodying another aspect of the invention,which is suitable for use in radial conveyors, including the radialconveyor 10, particularly but not exclusively for coupling the front andrear chassis parts 72, 70 of the conveyor apparatus 10. In the contextof a radial conveyor, the pivot joint 88 couples the radially movableconveyor 12 and chassis 16 to a base part (which in the illustratedexample is the bogie that includes the rear wheels) to allow relativepivoting movement about an in-use vertical axis, i.e. an axis that isperpendicular to the longitudinal and transverse directions of thechassis 16. Hence, the joint 88 facilitates the radial movement of theconveyor 12. In preferred embodiments where the chassis 16 is of thetype illustrated in FIGS. 8 to 10, the joint 88 preferably alsofacilitates the pivoting between chassis parts 70, 72 that allows thechassis 16 to be raised and lowered as described above.

The preferred pivot joint 88 comprises an upper part 89 and a lower part90 coupled together by a spindle 91. The spindle 91, which may comprisea pin, rod or other suitable component, defines a pivot axis about whichthe upper and lower parts 89, 90 can rotate relative to one another.When used in the radial conveyor 10, the pivot axis provided by thespindle 91 is the vertical axis about which the conveyor 12 and chassis16 can move radially. Each joint part 89, 90 typically includes a plate92, 93 (each having an aperture (not visible) for accommodating thespindle 91), the plates 92, 93 providing an interface between the jointparts 89, 90. Typically, a bearing 94 (having an aperture (not visible)for accommodating the spindle 91) is provided between the plates 92, 93.The bearing 94 may take any suitable form, e.g. plate or ring, and mayoptionally include ball bearings. In alternative embodiments the bearing94 may be omitted in which case the plates 92, 93 may serve as bearingsurfaces.

In preferred embodiments, the upper joint part 89 includes part of asecond pivot joint. In the illustrated embodiment, the second pivotjoint part comprises a sleeve bearing 95 for receiving a pivot pin (notshown). Alternatively, the upper joint part 89 may include a pivot pinfor coupling with a sleeve bearing. In any event, in embodiments wherethe pivot joint 88 is provided on a chassis 16 of the type shown inFIGS. 8 to 10, the second pivot joint may provide the pivoting betweenchassis parts 70, 72 that allows the chassis 16 to be raised and loweredas described above. Optionally, the lower joint part 90 may be similarlyprovided with part of a third pivot joint.

In preferred embodiments, one of the joint parts 89, 90 is fixed withrespect to the spindle 91, the other joint part 90, 89 being rotatableabout the spindle 91. In the illustrated example, the spindle 91 isfixed to the lower part 90, e.g. by pin 96 or other convenient fixing,and the upper part 89 is rotatable about the spindle 91. When used in aradial conveyor, the lower joint part 90 is fixed to the non-radiallymoving base part (i.e. the bogie in the illustrated example), while theupper joint part 89 is fixed to the radially movable chassis/conveyorassembly.

The pivot joint 88 includes a rotation sensor 97, preferably an absoluterotation sensor, that is capable of detecting the rotational, orangular, position of the rotatable joint part 89 with respect to areference position. The rotation sensor 97 may be of any conventionaltype, preferably but not necessarily a non-contact sensor. Examples ofsuitable sensors include optical rotation sensors (e.g. a reflectivesensor, an interrupter sensor, or an optical encoder), or a magneticsensor (e.g. a variable-reluctance (VR) sensor, eddy-current killedoscillator (ECKO) sensor, Wiegand sensor, or Hall-effect sensor). In theillustrated embodiment the sensor 97 is assumed to be a magnetic sensor.

The sensor 97 is configure to detect, and preferably to measure,rotational movement of the rotatable joint part 89 about the spindle 91.To this end, the sensor 97 may be provided on the rotatable joint part89 and be directed at a target 98 provided on the spindle 91.Alternatively, the sensor 97 may be provided on the spindle 91 and bedirected at a target 98 provided on the rotatable joint part 89. Inpreferred embodiments, the target 98 or the sensor 97, as applicable, isprovided on the end of the spindle 91 that protrudes into the rotatablejoint part 89, preferably on an end face (e.g. a top face in thisexample). Correspondingly, the sensor 97 or the target 98, asapplicable, is provided on the rotatable joint part 89 at a locationfacing, and preferably adjacent, the end of the spindle 91. Preferably,whichever of the sensor 97 or target 98 is provided on the rotatablejoint part 89 is located and positioned such that it is co-axial withthe spindle 91. In the illustrated embodiment, the sensor 97 is providedon the rotatable joint part 89 and the target 98 is provided on the topof the spindle 91.

The rotatable joint part 89 preferably includes a cavity or space 99into which the spindle 91 projects and in which its end is exposed, thesensor 97 and target 98 being located in the cavity/space 99.

The sensor 97 may be supported by a mounting structure 101, e.g. aplate. The structure 101 may include a cover 103 for covering the sensor97. Preferably, a housing structure 105 is provided around the cavity 99to protect the sensing part of the sensor 97 and the target 98 from theexternal environment. Conveniently the mounting structure 101 serves aspart of the housing structure 105.

In embodiments where the sensor 97 is a magnetic sensor, the target 98may comprise a magnet, which may be mounted on or incorporated with thespindle 91 or rotatable joint part 89 as applicable. Calibration of thesensor 97 with respect to the reference position may be performed in anyconventional manner, e.g. by aligning the sensor 97 with the magneticpoles of the magnetic target 98. In cases where the sensor 97 isoptical, the target 98 may comprise one or more markings (notillustrated), and the sensor 97 may be calibrated with respect to themarkings in any conventional manner.

In use, the rotation sensor 97 detects the angular position of therotatable joint part 89 with respect to the reference position. In thecontext of the radial conveyor, the sensor 97 produces an output signalthat may be used by a controller (not shown) to measure the radialposition of the conveyor 12 and so used to control the radial movementof the conveyor 12. This eliminates the need to provide stops to limitthe conveyor's radial movement.

The invention is not limited to the embodiment(s) described herein butcan be amended or modified without departing from the scope of thepresent invention.

1. A material processing apparatus comprising a material processingmachine pivotably coupled to a base by a pivot joint that allowspivoting movement of said material processing machine about a pivot axisthat is perpendicular to a ground surface, wherein said pivot jointcomprises an upper joint part coupled to said material processingmachine, and a lower joint part coupled to said base, said upper andlower parts being coupled together by a spindle that defines said pivotaxis and about which the upper joint part is rotatable with respect tothe lower part, and wherein said pivot joint includes a rotation sensorfor detecting an angular position of said upper joint part with respectto a reference position.
 2. The apparatus of claim 1, wherein saidmaterial processing machine is supported by a chassis, the chassis beingcoupled to said base by said pivot joint.
 3. The apparatus of claim 2,wherein said chassis includes at least one wheel assembly configured tosupport pivoting movement of said material processing machine and saidchassis about said pivot axis.
 4. The apparatus of claim 2, wherein saidmaterial processing machine is a conveyor.
 5. The apparatus of claim 1,wherein the rotation sensor is provided on either one of the upper jointpart or the spindle, and wherein a sensor target is provided on theother of the upper joint part or the spindle, the sensor being directedat the target.
 6. The apparatus of claim 5, wherein the target or therotation sensor is provided on an end of the spindle that protrudes intothe upper joint part, and wherein the other of the rotation sensor orthe target is provided on the upper joint part at a location facing theend of the spindle.
 7. The apparatus of claim 1, wherein said rotationsensor is a non-contact sensor.
 8. The apparatus of claim 1, whereinsaid rotation sensor is a magnetic rotation sensor.
 9. The apparatus ofclaim 1, wherein said upper joint part includes part of a second pivotjoint
 10. The apparatus of claim 1, wherein the rotation sensor isconfigured to generate an output signal indicative of the angularposition of said upper joint part, said apparatus including, or beingco-operable with, a controller configured to use said output signal todetermine an angular position of said conveyor and said chassis.
 11. Theapparatus of claim 1, wherein said base comprises at least one wheelassembly.
 12. A pivot joint for coupling a first part of a materialprocessing apparatus to a second part of a material processing apparatusto allow pivoting movement of said first part with respect to saidsecond part about a pivot axis that is perpendicular to a referencesurface, said pivot joint comprising an upper joint part for coupling tosaid first part, and a lower joint part for coupling to said secondpart, said upper and lower parts being coupled together by a spindlethat defines said pivot axis and about which the upper joint part isrotatable with respect to the lower part, and wherein said pivot jointincludes a rotation sensor for detecting an angular position of saidupper joint part with respect to a reference position.
 13. The pivotjoint of claim 12, wherein the rotation sensor is provided on either oneof the upper joint part or the spindle, and wherein a sensor target isprovided on the other of the upper joint part or the spindle, the sensorbeing directed at the target.
 14. The apparatus of claim 13, wherein therespective one of the target or the rotation sensor is provided on anend of the spindle that protrudes into the upper joint part, and whereinthe respective other of the sensor or the target is provided on theupper joint part at a location facing the end of the spindle.
 15. Theapparatus of claim 12, wherein said rotation sensor is a non-contactsensor.
 16. The apparatus of claim 12, wherein said rotation sensor is amagnetic rotation sensor.
 17. The apparatus of claim 12, wherein saidupper joint part includes part of a second pivot joint
 18. The apparatusof claim 12, wherein the rotation sensor is configured to generate anoutput signal indicative of the angular position of said upper jointpart, and being co-operable with a controller configured to use saidoutput signal to determine an angular position of said first part.
 19. Achassis for a material processing apparatus, the chassis comprising afirst end, a second end and an intermediate section between said firstand second ends, wherein the chassis comprises first chassis part thatincludes said first end, a second chassis part that includes said secondend, said first chassis part including a link structure that ispivotably coupled to said second chassis at a first pivot axis that runstransversely of the chassis and is located between first and second endsof the chassis to allow relative pivoting movement between the first andsecond chassis parts about said first pivot axis, said link structurebeing pivotable at said first chassis part about a second pivot axisthat is spaced apart and parallel with said first pivot axis, whereinsaid relative pivoting movement between the first and second chassisparts allows said intermediate section of the chassis to be lowered orraised between an operating state in which said intermediate section isrelatively raised, and a lowered state in which said intermediatesection is lowered with respect to said operating state.
 20. The chassisof claim 19, wherein a locking device is coupled between the linkstructure and the second chassis part and is operable between a lockingmode in which it prevents said relative pivoting movement between thefirst and second chassis parts, and an unlocked mode in which it allowssaid relative pivoting movement.